How to Check the Power Supply With a Multimeter. The power supply in your computer manages all of the power required to run each component of your computer. When this critical component begins to ...

Power on the computer. The multimeter should read between 11 and 12 volts. If it's too high or too low, the power supply is failing and needs to be replaced. Test pin 12 as well.

If you want to test the Power Supply Unit (PSU) of your Windows computer, use one of the methods mentioned in this post.

You can check the power supply on your PC by removing the side panel of its case, or by checking the manual that came with it.

How many Watts does your computer use? These Power Supply Calculators will help you measure your PCs total power consumption & calculate the energy use.